PiDP-8/I Software

    come from DEC's book "101 BASIC Computer Games." These are normally
    installed to `RKB0:` as `*.BA`, thus the option's name.

    (We considered naming it `--disable-os8-basic-games-and-demos`, but
    that's too long, and it can't be `--disable-os8-basic` because that
    implies that it is the OS/8 BASIC subsystem that is being left out,
    which is not even currently an option.)

*   **--disable-os8-cc8** - Leave out Ian Schofield's native OS/8 CC8
    compiler and all of its ancillary files.

*   **--disable-os8-chess** — Leave out John Comeau's
    [CHECKMO-II chess implementation][chess].




*   **--disable-os8-crt** — Suppress the [console rubout behavior][tty]
    enabled while building the OS/8 binary RK05 disk image. You
    probably only want to do this if you have attached a real teletype
    to your PiDP-8/I, and thus do not want video terminal style rubout
    processing.

*   **--disable-os8-dcp** — Leave out the DCP disassembler.

*   **--disable-os8-focal** - Do not install any version of FOCAL on the
    OS/8 system disk. This option sets `--disable-os8-uwfocal` and
    overrides `--enable-os8-focal69`, both discussed below.

*   **--disable-os8-fortran-ii** - Leaves out the FORTRAN II compiler,
    SABR, the linking loader (`LOADER`), the `LIBSET` tool, and the
    `*.RL` library files.  This option is ignored unless you also give
    `--disable-os8-cc8` because the OS/8 version of CC8 is built atop
    this subsystem.

*   **--disable-os8-fortran-iv** - Leave the FORTRAN IV compiler out.

*   **--disable-os8-init** - Do not install `RKB0:INIT.TX` or its “show
    on boot” script, `INIT.CM`.  Rather than disable the default on-boot
    init message, you may want to edit `media/os8/init.tx.in` to taste
    and rebuild.

#### --help

Run `./configure --help` for more information on your options here.


## <a id="os8di"></a>The OS/8 RK05 Disk Image

For the first several years of the PiDP-8/I project, the OS/8 RK05 disk
image included with the PiDP-8/I software (called `os8.rk05`) was based
on an image of a real RK05 disk pack that someone allegedly found in a
salvaged PDP-8 system.  Parts of the image were corrupt, and not all of
the pieces of software on the disk worked properly with the other parts.
It was also a reflection of the time it was created and used out in the

document.

[bdt2]:  https://tangentsoft.com/pidp8i/file/media/os8/al-4712c-ba-os8-v3d-2.1978.tu56
[cl]:    https://tangentsoft.com/pidp8i/doc/trunk/ChangeLog.md
[cs]:    https://tangentsoft.com/pidp8i/doc/trunk/doc/class-simh.md
[os8mf]: https://tangentsoft.com/pidp8i/file/media/os8
[tlrm]:  https://tangentsoft.com/pidp8i/doc/trunk/README.md


## <a id="os8ti"></a>The OS/8 TU56 Tape Image

As with the [OS/8 disk image](#os8di), this distribution’s build system
can create custom TU56 tape images from pristine source media.  This
replaces the old `os8.tu56` binary image previously distributed with
this software.

The build system actually creates four such tape images according to a
2×2 matrix of choices:

*   **--boot-tape-version** — The default value is “`v3f`”, meaning
    that the boot tape is based on OS/8 V3F. Give “`v3d`” to boot from
    a OS/8 V3D tape instead. See the wiki article [OS/8 V3D vs
    V3F][os8ver] for the implications of this choice.

*    **--boot-tape-config** — The default value is “`tc08`”. Give
    “`td12k`” to use a tape image configured with the TD12K DECtape
    controller driver built in. See the wiki article [TC08 vs
    TD12K][os8td] for the reason you’re given a choice here.

[os8td]:  https://tangentsoft.com/pidp8i/wiki?name=TD8E+vs+TC08
[os8ver]: https://tangentsoft.com/pidp8i/wiki?name=OS/8+V3D+vs+V3F



<a id="overwrite-setup"></a>
## Overwriting the Local Simulator Setup

When you run `sudo make install` step on a system that already has an
existing installation, it purposely does not overwrite two classes of